[Ozone holes: prognosis of human photo-ecology. Protection and sensitization]. / Ozonovye dyry: prognoz fotoékologii cheloveka. Zashchita i sensibilizatsiia.

Photoecological consequence of ozone holes are considered. Analysis of the total UV-radiation intensity and the short-wave edge of atmospheric transmittance depending on ozone content is presented. Characteristic times of some photodamages to skin and eyes have been estimated under ozone content reducing. A role of photosensitizers including drugs in phototoxical effects is discussed. Possible ways of photoprotection are considered.

[The systemic response of antioxidant enzymes to the oxidative stress induced by irradiation at low doses]. / Sistemnyi otvet antioksidantnykh fermentov na okislitel'nyi stress, vyzvannyi oblucheniem v malykh dozakh.

As a result of total chronic gamma irradiation of mice (137Cs, 0.6 cGy/day, 9 days) the functioning of superoxide generation and utilisation systems in liver were disturbed. The regulatory links between the activities of superoxide dismutase and glutathione peroxidase are found to be maintained. Postradiation effects were more expressed for a total dose of 1.2 cGy than for a dose of 5.4 cGy, providing support for the hypothesis of delayed reparation as a reason of harmful action of low-dose irradiation.

[The antioxidant status of the seeds in populations of the great plantain (Plantago major L.) growing in an area exposed to the Balakovo Atomic Electric Power Station and to chemical enterprises]. / Antioksidantnyi status semian populiatsii rastenii podorozhnika bol'shogo (Plantago major L.), proizrastaiushchikh v raione deistviia Balakovskoi AES i khimicheskikh predpriiatii.

The results of the determination of radionuclide and chemical (multielement analysis) soil pollution are presented. The data on antioxidant status of plantain (Plantago major L.) in conjunction with the data on radionuclide and chemical pollution are analyzed. The most significant decrease in antioxidant activity of plant seeds was observed in areas situated along the most frequent wind direction in the region in summer 1998. It is suggested that lower antioxidant status is caused by the chronic radionuclide release on the chemically polluted territories.

[Evaluation of the consequences of stress factors on plant seeds growing in a 30-km zone of Balakovo AES]. / Otsenka posledstvii vliianiia stressovykh faktorov na semena rastenii, proizrastaiushchikh v 30-kilometrovoi zone Balakovskoi AES.

The effect of stress factors (small doses of radiation and maximum temperatures in the econiche of the tested plants (tmax)) as well as aging on pea seeds, both acting independently and in combination, is estimated. Here we evaluate the influence of oxidizing stress on pea seeds in the laboratory (gamma-irradiated with 7 cGy at 0.3-19.1 cGy/h, tmax approximately 30-32 degrees C) and on natural plantain seeds collected in a 30-km zone of NPP (radiation exposure approximately 15 R/h, tmax approximately 38-40 degrees C). We have mathematically modeled CAs frequencies in root seedlings meristeme by invoking an enhancing factor transmitted from cell to cell. It is shown under the stress conditions: 1) CA frequency decreases whereas the fraction of inviable seeds (IS) increases, the dependence of IS on CA frequency being inversed; 2) a stimulation of proliferation of cell was observed; 3) a bystander effect appears; 4) antioxidative status (AOS) of seeds influences on adaptation on the all levels of the organization; 5) IS increases up to 73-80% under the combined effect of radiation and heat stresses.

[Comparative effectiveness of some medicinal substances as acceptors of superoxide radicals]. / Sravnitel'naia éffektivnost' nekotorykh lekarstvennykh preparatov kak aktseptorov superoksidnykh radikalov.

The effect of about 30 medicines and some other compounds on the yield of the riboflavin sensitized glycyltryptophan photochemiluminescence occurring at the participation of superoxide and glycyltryptophan peroxide free radicals in solution has been studied. Some of the investigated compounds decrease the chemiluminescence yield as a result of their reactions with superoxide and gly-try peroxide radicals. The concentrations of compounds decreasing the chemiluminescence yield by 2 times were obtained. The estimation of the rate constants for a few compounds is given. It is shown that rutin, quercetin, ascorbic acid, aethamzilat, analgin, paracetamol, serotonin and butadione are most effective among the investigated medicines.

[Antioxidant properties of a series of extracts from medicinal plants]. / Antioksidantnye svoistva riada ékstraktov lekarstvennykh rastenii.

Investigation of antioxidant properties of some plants was carried out. A group of plants affected human central nervous system was studied in detail. Efficiency of plants as antioxidants was tested by the influence of their extracts on the yield of photochemiluminescence of Gly-Trp solutions. Antioxidant properties were examined under conditions when their own absorption was minimized. Riboflavin as additional sensitizer was used in this experiment for superoxide generation. The antioxidant effect was evaluated with regard to single dose of plant extracts and their concentration in human organism. The effect decreases in the following consequence: Hypericum > Eleutherococcus > Rhodiola > Leonurus > Aralia > Valeriana > Echinopanax > Schizandra > Panax gin-seng.

[Photosensitizing and photoprotective properties of extracts from groups of medicinal plants]. / Fotosensibiliziruiushchie i fotoprotektornye svoistva ékstraktov gruppy lekarstvennykh rastenii.

Investigation of photosensitization and photoprotection induced by plant extracts was carried out. A group of plants affected human central nervous system was studied in detail. Efficiency of plants as photoprotectors and photosensitizers was tested in the frame of the influence of their extracts on the yield of photochemiluminescence of Gly-Trp solutions. Photosensitization was studied under irradiation with light lambda > 280 nm and lambda > 320 nm, as well as with monochromatic light lambda=313, 365, 405 and 436 nm. All of the plants studied acted as photoprotectors in low concentration and as photosensitizers in high concentration. The efficiency of photoprotection and photosensitization was evaluated with regard to single dose of plant extracts and their concentration in human organism. The effect decreases in the following consequence of plants: Leonurus > Hypericum > Aralia > Schizandra > Echinopanax > Eleutherococcus > Valeriana > Panax ginseng. Photosensitization is due to the components of plant extracts which have strong absorbtion at the high wavelength range. The mechanism of photosensitization was suggested. Singlet oxygen generated by photoexcited compounds is the main species resulted in chemiluminescence. Superoxide radicals does not contribute significantly to the chemiluminescence formation.

[Photosensitization and photoprotection by some drugs, metabolites and other compounds]. / Fotosensibiliziruiushchie i fotoprotektornye svoistva nekotorykh lekarstvennykh preparatov, metabolitov i drugikh veshchestv.

Photosensitizing and photoprotecting efficiency of about a hundred of compounds, mainly drugs, was studied. The method based on chemiluminescence occurred along with photooxidation of glycyltryptophan under irradiation in UVB range in solution was used for testing. As a measure of photosensitizing efficiency the concentration of photosensitizer which induced two-fold increase of chemiluminescence intensity was chosen. The most effective photosensitizers are riboflavin, FAD, furagin, psoralene, vicasol, benzobarbital, mydocalm, angelicyn, furadonin, ethacridin, diazolin, folic acid. With regard to pharmacological doses of drugs in organism more dangerous sensitizers (in descending order) are p-aminosalicylic acid, furagin, riboflavin, benzobarbital, thiopental, chloramphenicol, nicodin, mydocalm, furadonin, oxolonic acid, furazolidone, psoralene, nicotinamide and diazolin. Photoprotecting effect was described by the concentration at which chemiluminescence intensity decreased twice. The most effective photoprotectors are etamsilat, quercetin, ftivazid, chlorpromazine, diprazine, thioridazine, aminophenazone, oxaphenamide. Concentration dependence for some of these drugs (etamsilat, chlorpromazine, diprazine, thioridazine) is non-monotonous: they inhibit photooxidation in low concentration (about 10(-7)-10(-6) M), but at higher concentrations (10(-5)-10(-4) M) photosensitization dominates over photoprotection.

[Phenothiazine drugs as photosensitizers and photoprotectors]. / Lekarstvennye preparaty iz riada fenotiazinov kak fotosensibilizatory ifotoprotektory.

The photosensitizing properties of eight N-alkylated phenothiazine neuroleptic drugs were studied. The experiments were carried out in a model system based on photooxidative chemiluminescence of Gly-Trp peptide in aqueous solution. Under irradiation with light longer than 280 nm, all the studied phenothiazine derivatives decrease the chemiluminescence intensity at low concentrations and enhance it at high concentrations. Phenothiazine derivatives is likely to be due to superoxide and/or Gly-Trp free peroxide radicals. Photosensitization begins to dominate over protection at concentrations which are different for various phenothiazine derivatives compounds and lie in the range 10(-6)-10(-5) M. The photosensitizing efficiency decreases in the order: Thioproperazine, Trifluoperazine Hydrochloride, Alimezine, Thioridazine Hydrochloride, Levomepromazine Hydrochloride, Promethazine Hydrochloride, Periciazine, Chlorpromazine Hydrochloride. It was shown that photooxidation of Gly-Trp sensitized by phenothiazine derivatives occurs via singlet oxygen formation.

[Antioxidant properties of plant extracts]. / Antioksidanthye svoistva gruppy ekstraktov lekarstvennykh rastenii.

Investigation of antioxidant properties of some plants was carried out. A group of plants exhibited antimicrobial activity was studied in detail. Efficiency of plants as antioxidants was tested by the influence of their extracts on the yield of photochemiluminescence of Gly-Trp solutions. Antioxidant properties were examined under conditions when their own absorption was minimized. Riboflavin as additional sensitizer was used in this experiment for superoxide generation. The antioxidant effect was evaluated with regard to single dose of plant extracts and their concentration in human organism. The effect decreases in the following consequence: Hypericum perforatum > Potentilla erectra > Ledum palustre > Plantago major > Salvia officinalis > Chamomilla recutita > Arctostaphylos uva.

[Effects of plant growth regulators ambiol and phonk: biolphysical aspects]. / Biofizicheskie aspekty deistviia reguliatorov rosta ambiola i fonka.

The antioxidative activity of two plant growth promoters, ambiol and phonk, in a model system of photo-induced glycyltriptophane oxidation was measured. It was shown that ambiol has a significant antioxidative activity, whereas phonk is a weak antioxidant. The effects of these compounds on DNA conformation were studied in vitro and in vivo (on wheat seed shoots). In vitro ambiol had a stronger effect as compared with phonk, whereas in vivo the latter produced a more essential effect than ambiol. The assumption was done that both compounds affect indirectly the genome expression activity. Possible mechanisms of biological activity of each compound are discussed.

[Superoxide dismutase activity and photosensitizing properties of 2,5-dihydroxybenzolsulfonate]. / Superoksiddismutaznaia aktivnost' i fotosensibiliziruiushchie svoistva 2,5-digidroksibenzolsul'fonata.

2,5-dihydroxybenzolsulphonate was shown to actively interact with the superoxide radical O2-. formed under UV-radiation of glycyltryptophan aqueous solutions or under visible light illumination of glycyltryptophan and riboflavine. The constant of the rate of reaction of 2,5-dihydroxybenzolsulphonate with O2-. was determined to be equal to 1.3 X 10(9) M-1s-1. A photosensitized effect of 2,5-dihydroxybenzolsulphonate under illumination with the light with 280 nm was found. The sensitization efficiency of glycyl-tryptophan oxidation increases when the experiments are carried out in the oxygen atmosphere.

[Photosensitizing properties and antioxidant activity of furagin--an antimicrobial drug that is a derivative of nitrofuran]. / Fotosensibiliziruiushchie svoistva i antioksidantnaia aktivnost' furagina--antimikrobnogo lekarstvennogo preparata, proizvodnogo nitrofurana.

Photosensitizing effect of antimicrobial drug nitrofuran derivative--furagin N-(5-nitro-2-furil)-allylidencamino-hydantoin) under irradiation with light longer than 280 nm was found. The method of investigation is based on photochemiluminescence of Gly-Trp peptide in aqueous solution. Maximum photosensitizing efficiency was observed at the furagin concentration 0.08 mM when chemiluminescence yield was 33 times greater than photochemiluminescence of Gly-Trp peptide in absence of drug. It was shown that photochemiluminescence sensitized by furagin occurred via free radical way. Life time of the triplet state of furagin determined by flash photolysis was 40 microseconds. A comparison of experimental data with kinetic calculation allowed us to estimate the rate constant of triplet quenching by oxygen ((2.2 +/- 0.3)10(8) M-1.s-1) and the total rate constants of physical quenching and chemical reaction with Gly-Trp peptide ((2.0 +/- 0.4)10(8) M-1.s-1). It was also found in experiments with photochemiluminescence of Gly-Trp peptide sensitized by riboflavin (irradiation with monochromatic light 436 nm) that furagin possesses antioxidant properties twice reducing the intensity of chemiluminescence at the drug concentration 0.029 mM.

[Potentially dangerous photosensitizers among drugs and medicinal plant extracts]. / Potentsial'no opasnye fotosensibilizatory sredi lekarstvennykh veshchestv i ékstraktov lekarstvennykh rastenii.

The review deals with photosensitizing properties of drugs and plant extracts. Some compounds are able to cause side effects such as phototoxicity and photoallergy. Revealing and study of harmful photosensitizers is actual problem in connection with changing photoecological situation.

[Changes in the intensity of free-radical reactions in the organs of rats under hypokinetic stress and with protection by the delta sleep-inducing peptide and its tyrosine-containing analog]. / Izmeneniia intensivnosti svobodnoradikal'nykh reaktsii v organakh krys pri gipokineticheskom stresse i zashchite del'ta-son-indutsiruiushchim peptidom i ego tirozinsoderzhashchim analogom.

Dynamics of the hypokinesia-induced changes of free radical and malonic dialdehyde content in brain, the changes of respiratory chain state and superoxide dismutase activity in liver of rats has been studied using ESR technique and biochemical methods. The effect of the preliminary injection of DSIP and its analogue ID-2 on these dynamics has also been studied. Using a model system constants of the interaction between DSIP or ID-2 and O2-. have been determined. The data point to the antioxidant effect of the administration of the peptides before hypokinesia. This suggests that the effect involves in mechanisms of the anti-stress action of these peptides.

[The kinetics of the chemical modification of DNA radiation transformations in multicomponent systems. An analytical review]. / Kinetika khimicheskoi modifikatsii radiatsionnykh prevrashchenii DNK v mnogokomponentnykh sistemakh. Analiticheskii obzor.

Most probable ways of chemical protection and sensitization of DNA macromolecules under the effect of ionizing radiation in aqueous solutions have been investigated. A kinetic model in proposed, based on the experimental data available, that consists of 25 reactions involving DNA (D), protein (P), glutathione (G), oxygen (O2), various protectors and sensitizers (A), active products of water radiolysis (O, e (H)), free and peroxide radicals of DNA and other components, and peroxides. General and partial rates of radiation transformations of DNA, depending on D, P, G, O2 and A concentrations are expressed in analytical terms. The relationships obtained are used for a qualitative description of some biological effects of ionizing radiation that is: a difference in radiosensitivity of different organs and tissues and its alteration during the cell cycle; oxygen effect; and the concentration relationships of the radioprotection and radiosensitization coefficients.